Ads that use dns cnames to bypass block lists. Only Firefox has an API for this.
Ads that previously were blocked at the HTTP Response level. ManifestV3 removed this API.
A world where the number of ad rules exceeds the new limit. Which is 500 dynamic rules, 50 static rulesets, 30,000 rules. This may sound high but its not.
This is really really important now that server side tracking is rolled out at the major Ad providers. Keeping up a block list of the custom domains every site uses to mask their tracking will lead to an unsustainable cat and mouse game.
I've got used to the google lens thing. If you click the address bar then the lens icon and then highlight part of the page it visually analyses it, ocr's text, searches for the text, optionally translates it etc. I use it all the time because people will post text in image form.
It's not really a "switch" type of decision for me. That implies friction or commitment. I have every major browser installed, like a bowl of different flavored jelly beans. I pick whichever I want that day. Firefox isn't my favorite. A bit lower framerate rendering, a few missing features, a bit less extensions that I like. There's currently zero advantages I know of that would compel me to ever open firefox. They could literally release any novel feature that could win me over - I have no loyalty - they just don't have anything special.
Some sites have issues with Firefox, it is rare, but it happens. Some streaming services may not work at full resolution on Firefox because of DRM. You may also want sync with your Microsoft or Google account and not your Firefox account (if you even have one) for whatever reason.